key: cord-0741761-rv3rptyv authors: Mohseni, Houra; Amini, Shirin; Abiri, Behnaz; Kalantar, Mojtaba; Kaidani, Masoumeh; Barati, Barat; Pirabbasi, Elham; Bahrami, Faezeh title: Are history of dietary intake and food habits of patients with clinical symptoms of COVID 19 different from healthy controls? A case-control study date: 2021-01-29 journal: Clin Nutr ESPEN DOI: 10.1016/j.clnesp.2021.01.021 sha: e65f71d4fc92b1afadd62177298030be3f0c7fdc doc_id: 741761 cord_uid: rv3rptyv Background Coronavirus disease 2019 (COVID-19) is an infectious disease that put unprecedented significant strain on clinical services and healthcare systems. The aim of the present research was to assess dietary food groups and also food habits of patients with clinical symptoms of COVID 19 and healthy controls. Methods This case-control research was carried out on 505 participants (279 subjects with clinical symptoms of COVID-19 and 226 controls), in age 18 to 65 years. Dietary food group’s intake last year was investigated by a food frequency questionnaire. Food habits were asked by a general information questionnaire. The strength of the association between food group’s intakes with the odds ratios (ORs) of COVID-19 was assessed using Logistic regression models. Results After adjusting for physical activity in the logistic regression models, intake of dough and yogurt had a significantly protective role on occurrence of COVID19, (OR= 0.62; 95% confidence interval (CI) = 0.44-0.87; P= 0.006), (OR= 0.74; 95% CI = 0.56- 0.98; P= 0.044), respectively. No significant differences were seen in food habits between the two groups in the last years ago. Conclusions High risk population for COVID19, advised to consume enough amount of yogurt and dough at the time of this pandemic. China in late December 2019 [1] . The ongoing pandemic has resulted in more than 17.5 million confirmed cases and 677, 000 deaths worldwide and there have been almost 92, 000 deaths in the Asia Region up to 1 August 2020 [2, 3] . Coronaviruses belong to β-coronaviruses and are transmitted through secretions of infected people such as saliva and respiratory secretions or their respiratory droplets [4, 5] . The severity of clinical symptoms in positive COVID-19 patients is varied, ranging from asymptomatic to acute respiratory distress syndrome and multi-organ dysfunction [6] . Previouse researches reported male sex, older age, and chronic diseases such as diabetes, hypertension, and obesity as the risk factors for severe clinical symptoms of COVID-19 [7, 8] . After infection with SARS-CoV-2, the uncontrolled response of the immune system against the virus causes damage of pulmonary tissue, functional impairment, and restricted lung capacity. Apart from pneumonitis in the early phase, 10-14 days after the virus infection, sudden reduction of lymphocytes like natural killer (NK) cells in blood along with severe inflammatory reaction happened that is called cytokine storm. In the critical condition, spleen and lymph nodes are atrophied and number of lymphocytes decrease drastically which leads the patient to hypercoagulability, thrombosis, and multi-organ damage [9] . Evidence demonstrated that appropriate nutrition plays a role in the improvement of the immune system and malnutrition resulted in increased rate of infections [10, 11] .Nutrients requirements are provided by dietary sources or body stores. Subclinical deficiencies of micro and macro nutrients may have a negative effect on body immune responses [11] . It is proposed dietary intake of some bioactive foods may enhance immune System to fight against COVID19 [12] . A recent review has emphasized on optimum nutrition status as important factor for a wellfunctioning of immune system against viral infections [13] and another review study has J o u r n a l P r e -p r o o f highlighted critical role of diet and relevant nutrients to effectively diminish inflammation and oxidative stress, consequently reinforcing the immune system during the COVID-19 crisis [14] . A new invitro study that assessed the effects of coronavirus on lung tissues suggested those nutrition recommendations have an important role in reducing damages of coronavirus to the lungs [15] . Up to now, no research study has been carried out to evaluate the dietary intakes of COVID19 patients. Hence, the aim of the present research was to assess and compare history of dietary food group's intake and also food habits between patients with clinical symptoms of COVID 19 and healthy controls. In the present retrospective case-control research, totally 505 participants (279 patients with clinical symptoms of COVID-19 and 226 exposures to virus and healthy controls), in age 18 to 65 years, were investigated. Participant with positive nasopharyngeal swab testing for SARS-CoV-2, hospitalized and/or referring to the outpatient clinic of Khatam Al-Anbia Hospital, in Shoushtar city and Razi Hospital, in Ahvaz, Khuzestan province, in Iran, were considered for the case group, between June and August 2020. The COVID19 clinical symptoms in the case group were confirmed by a physician according to clinical symptoms and laboratory and radiographic findings, by referring to patients' medical records. The telephone number of the subjects was taken from the hospital and contacted them. Patients were asked to participate in the study after recovery if they wished. In cases that they may have not been able to answer that questions honestly, we asked from near family members of patients to assist the subjects in completing the questionnaires. J o u r n a l P r e -p r o o f Participants in the control group was exposure to the virus, but asymptomatic and with negative nasopharyngeal swab testing for SARS-CoV-2. Participants in both case and control groups were selected from general populations, physicians, nurses, midwives and staff working in hospitals and medical centers, from June to August 2020. Both the case and the control groups were matched in terms of gender, age, and body mass index (BMI), and job. Demographic data including gender, age, educational levels, employment and economic status, marital status, history of smoking, history of chronic diseases and history of nutritional supplements intake were collected by questionnaire. Anthropometric measurements including weight and height were also measured with an accuracy of 0.5 kg and 0.1 cm, respectively. BMI J o u r n a l P r e -p r o o f was calculated based on the following formula: body weight (kilogram) divided by squared height (meter 2 ). The physical activity level was investigated by the short form of the international physical activity questionnaire (IPAQ).The total metabolic equivalent (METs) calculated via usual physical activity of participants. Then participants, based on the levels of activity, were classified into three groups: 1-active, 2-minimally active and 3-inactive. The validity and reliability of IPAQ have been confirmed in 12 countries [16] . Its reliability and validity have also been confirmed in Iran [17] . A food frequency questionnaire (FFQ) which was designed and validated for Iranian population [18] and used in Iranian studies, previously [19, 20] was used, and participants' foods that were consumed, in a last year asked by a trained interviewer. The portion sizes for units of each food group were defined according to the USDA portion sizes in the questionnaire [21] . The frequency of units consumed from each food group (based on the food pyramid) was recorded in forms of daily, weekly, monthly, yearly or never and then converted to a unit per day. The groups of foods included: cereals and breads (including rice, pasta and bread), dairy (including milk, yogurt, fermented dairy drink (doogh), cheese and ice cream), meat and alternatives (including all kinds of meat, legumes, and eggs), fruits and vegetables. Also, the amount of consumption of fatty foods, the type of dairy (low-fat dairy with less than 1.5% fat, medium-fat dairy with 2.5% fat, high-fat dairy with more than 2.5% fat), and the type of oils (Animal oil, olive, canola, sunflower and corn, olive and frying oil) that were consumed were asked. Amount of consumption of cakes and biscuits, soft drinks and fast foods was also J o u r n a l P r e -p r o o f recorded in forms of daily, weekly, or monthly in this questionnaire and then reported qualitatively (low, medium, and high). The Kolmogorov-Smirnov test was used to the evaluate normality distribution of all variables. Data with normal or non-normal distribution were reported as mean±standard deviation (Mean±SD) and median (25 th , 75 th percentiles), respectively. Independent t-test in the data with normal distribution and Mann-Whitney U in the data with non-normal distribution were used to compare the differences between the case and control groups. The residual method was used for adjusting the total energy intake [22] . Categorical variables were also compared using Chi-squared test. Logistic regression models were used to estimate the strength of the association between food group intakes and the odds ratios (ORs) of COVID19. The associations were assessed in crud OR and then, were corrected with effects of factors, including BMI, energy intake, taking nutritional supplements and physical activity in two additional models. The statistical analysis was carried out using SPSS version 17.0 (SPSS Inc, Chicago, IL, U.S.A.). Two-sided P-values with P<0.05 was considered statistically significant. Of the 517 enrolled subjects, 7 subjects (4 in the control and 3 in the case groups) were excluded from the study due to incomplete reporting by the questioner. In addition, 2 subjects from the controls and 3 from the cases were also excluded due to over-reporting in food groups. Eventually, the data of 505 subjects (226 controls and 279 cases) were analyzed. The demographic characteristics are shown in Table 2 , there were significant differences in the mean dietary intakes of dough between the COVID19 and the controls (P= 0.012). Cases had lower doogh intake than the controls. Table 4 , most participants consumed low numbers of biscuits and cakes, soft drinks and fast foods, and there were no significant differences between the patients with clinical symptoms of COVID19 and controls in the consumption of these terms. Furthermore, there were no significant differences between the dairy type, the amount of fat in foods and usual types of used oils between the case and control groups (Table 5) J o u r n a l P r e -p r o o f In the present study, we aimed to compare dietary food groups, and nutritional habit in patients with clinical symptoms of COVID 19 and healthy controls. Moreover, we assessed the associations between dietary intake of food groups and the incidence of clinical symptoms of COVID 19. To the best of our knowledge, this is the first case-control study in this area. We observed an effect for the adequate consumption of doogh and yogurt, last year and occurrence of COVID19 clinical symptoms. In the more population, due to lactose intolerance, milk consumption is low and yogurt and fermented dairy are mainly used as sources of dairy products. Dairy products are a good source of high quality protein, B2 and probiotics. The probiotics in yogurt and doogh and fermented milk may play a role in modulating the immune system against the virus. Some studies suggest the potential role for probiotics in the modulation of the immune system that can balance the inflammatory response and increase the response to viruses [23, 24] . Another study suggested bioactive peptides derived from fermented milks with Lactobacillus plantarum strains disrupt viral spike protein [24] . Although, most of the findings suggest that SARS-Cov-2 virus is more likely transmitted through the respiratory route, but many data also suggest that the intestine could play an appropriate role in the pathogenetic evolution of this viral disease [23] . To the best of our knowledge, this research was the first case-control study that assessed and J o u r n a l P r e -p r o o f Not applicable. The data is available and if needed, provided by the corresponding author. The authors declare no conflict of interest. J o u r n a l P r e -p r o o f P-value <0.05 was considered significant. *p < 0.05, **p < 0.01 WHO declares COVID-19 a pandemic Unusual Presentation of COVID 19-A Case report Updated understanding of the outbreak of 2019 novel coronavirus (2019-nCoV) in Wuhan COVID-19 outbreak-Diabetes aspect and perspective Consistent detection of 2019 novel coronavirus in saliva Coronavirus disease 2019 (COVID-19): a perspective from China Presenting characteristics, comorbidities, and outcomes among 5700 patients hospitalized with COVID-19 in the New York City area Clinical characteristics of coronavirus disease 2019 in China COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation Impact of diet on human intestinal microbiota and health Enhancing immunity in viral infections, with special emphasis on COVID-19: A review Food ingredients and active compounds against the Coronavirus disease (COVID-19) pandemic: a comprehensive review Optimal nutritional status for a wellfunctioning immune system is an important factor to protect against viral infections Strengthening the Immune System and Reducing Inflammation and Oxidative Stress through Diet and Nutrition: Considerations during the COVID-19 Crisis Treatment Strategies for Reducing Damages to Lungs In Patients with Coronavirus and Other Infections. Available at SSRN 3533279 International physical activity questionnaire: 12-country reliability and validity 7-day, long form of the International Physical Activity Questionnaire: translation and validation study Reliability and relative validity of an FFQ for nutrients in the Tehran lipid and glucose study Comparison of food intake and body mass index before pregnancy between women with spontaneous abortion and women with successful pregnancy Relationship of constipation and irritable bowel syndrome with food intake, anthropometric measurements and eating behaviors in male students Nutrition and depression: implications for improving mental health among childbearing-aged women Total energy intake: implications for epidemiologic analyses Supplementation, Probiotics, and Nutraceuticals in SARS-CoV-2 Infection: A Scoping Review Safety of foods, food supply chain and environment within the COVID-19 pandemic The authors wish to thank all participants and the personnel of Khatam Al-Anbia Hospital.